Refrigerant compressing unit



March 24, 1936. J R. REPLOGL 2,o35,276

REFRIGERANT COMPRES S ING UN I T Filed May 5, 1932 5 Sheets-Sheet l I I I I I I I I I I I I I I I I I I I I I 1 I I I I I I I INVENTOR ATTORNEYSL March`24, 1936.

REFRIGERANT COMPRESS ING UNIT .Filed May 5, 1932 5 Sheets-Sheet 52 A ORNEYS' J. R. REPLO'GLE 2,035,2 76 I.

Patented 24, 1936 uNirD sT'ATEs p aosaz'is REFRIGERANT ooMrnEssmG UNIT John R. Replogle, Detroit, Mieli., assignor, by mesne assignments, to Copeland Refrigeration Corporation, Mount Clemens, Mieli., a. corporation of Michigan Applicafien May 5, 1982,' serial No. 809,480' 1'1 claims. (cl. 280-206) This invention relates generally to motor compressor units and has particular relation ,to motor compressor units for-refrige'ration purposes.

An object of the invention is to provide a 5 simple, compact and eficient refrigerating apparatus `power unit embracing a compressor having a crankcase provided with an extension for the reception of a motor for driving the compressor and with both. the compressor casing and the extension provided with removable end wls for rendering the power unit parts access1 e.

Another object of the invention isA to so construct a refrigerating mechanism power unit that all of the Working parts thereof will be automatically lubricated'by cirqulating oil within the system and 'without the necessity for the employment of special oil pumping mechanism ordinarily required for this purpose.

20 Another object of the invention is to provide for the dissipation of the heat generated by the working parts of a motor compressor unit With'- out materially superheating the circulating working fluid employed in the refrigerating system and thereby increasing the volume of the' latter before it has reached the eompressing mechanism of the unit.

Another object of the invention is to provide a plurality of zones in the interior of a motor 30 compressor unit in one. of which a relatively .stagnant body of refrigerating fluid is maintained in a highly superheated state for conducting away the heat generated by the electrical energy dissipated within the motor of the unit but, by

'35 reason of the relative'isolation of such fiuid from the other zones, the'superheating and condensing of working fluid does not materially interfere With the operation of the system.

The particular embodiment of the invention 40 disclosed herein for the purpose of illustration v comprises a refrige'rant compressor having a finned extension formed 'on the casing thereof in which is contained an electric motor separated from the compressor by an end wall of the crank- 45 case of the latter. This separating end wall and an end plate secured removably upon the finned extension are provided with bearings'for supporting a hollow shaft on which the rotor part of the motor is journaled between the bearings.

50 This shaft ccnstitutes an extension of the compressorshaft which is rotatably supported in the compressor crankc-ase in one of the aforesaid bearings formed therein.` The interior of this shaft is connected directly with the refrigerant 55 evaporating unit of the system in which the power unit is employed and also with the suction side of the compressor. Also theinterior of the shaft is connected with the motor containing compartment of the extension vforjthe purpose of readmitting the oil collected within such compart- 5, ment to the fluid circulating part of the system and for equalizing the pressure of the compartment with the system. This connection, however, is such that there is only a small quans tity of' -working fluid conducted 'therethrough 10 The oil collected within the shaft is automatically distributed and supplied by 'the operation ofv the mechanism for lubricating and cooling the working parts in the interior o f'the casing and the extension.

An eccentric crank, formed on the compressor shaft, supports a connecting rod for Operating a piston which ismounted for reciprocation in the compressor cylinder and this crank and other moving mechanism of the compressor is balanced by a weight secured on the end `of the shaft in opposite relation thereto. .The compressor is provided With a valve plate and a head, the valve plate having a discharge valve arranged therein which cooperates with a suctionvalve arranged in the -piston'for eifecting the operation of the compressor.

The. electric motor within the extension embraces a main winding, a startingiwinding and a generator winding the latter of which generates the current as the motor attains its normal speed' for operating a switch to open the'starting winding circuit. 'The conductors for these various Wndings pass through terminals formed 'in a motor compressor unit embracing the principles of this invention; r

Fig. 2 is a cross-sectional view of a. portion of the refrigerator structure disclosed by Fig.`1 and illustrating particularly an end elevational view taken from the left hand side of the motor com- Fig. 4 is a transverse sectional view through the oompressor portion of the motor oompressor unit;

Fig. 5 is a horizontal sectional view of the compressor taken substantially on line 5-5 of Fig. 4;

li'ig.l 6 is a fragmentary horizontal sectional view of the oompressor taken slightly below'the plane of Fig. 5 on line 5-6 thereof and illustrating particularly the discharge valve of the compressor;

Fig. 'Z is a fragmentary cross-sectional view of the motor oompressor unit casing showing particularly the terminals by which electrical energy is supplied to the electrical motor therein;

Fig. 8 is an end elevational view of an oil disbalancing element employed in the motor compressor unit as it might appear looking in the direction of the arrows from line |0-||| of Fig. 3;

Fig. 11 is a fragmentary side elevational view of the balanoing element shown by Fig. 10;

Fig. 12 is 'a cross-sectional viewl through the balancing element as it might appear in .the plane of line |2-|2 in li'ig.v 10.

Fig. 13 is a fragmentary oross-sectional view on line |3-l3 of Fig. '7.

Figs. 14 and 15 are illustrations of slightly dif-` ferent forms of motor oompressor units embracing the principles of the invention.

Referring pairticularly to Figs. 1 and 2, the invention is embodied in-a refrigerator IS embracing a heat insulating cabinet |,1 outside of which is formed a machine compartment |8 which occupies the upper region in the rear of the refrigerator and is surrounded by an exterior lining 2| which also surrounds the cabinet 1. Along the rear of the refrigerator |5 the lining 2| is provided with an opening 22 through which a refrigerant condensing unit 23 located in the machine compartment is inserted and removed.

At-the front of the machine compartment |8 the insulating cabinet |1 is provided with an outwardly removable vertically disposed wall section 24 arranged on one side of the cabinet and to the opposite verticaledges of which are secured corresponding sides of vertically disposed portions of angle members 25. Horizontally disposed portions 21 of the angle members 25, formed by bending the members rearwardly at an angle of approximately 90 degrees, extend outwardly along the upper surface of the wall of the cabinet |1 forming the lower limit of the machine compartment |8. The laterally projecting portions of the vertical portions of the angle members 25 extend oppositely from the removable wall section 24 and thus provide abutments engaging theadjacent edges of the cabinet |6 for limiting the inward movement of the wall section 24.

Extending in spaced .relation across the upper V ;surfaces of the angle members 21 and substanjtially from one end of the compartment |8 to another: is a pair of channel members 23 which are secured to the laterally extending portions of the angle 'members 21 by bolts 29g. On the ends of these membersremote from the removable wall section 24 is secured a refrigerant'condenser 3| embracing a plurality of sinuously wound and inter'connected conduit sections 32 disposed one above another and supported adjacent the op-4 aosazve posite ends thereof by a spaced pair of supporting plates 33. The lower ends of the supportingipl z-ites are bent laterally as is indicated at 34 and are there secured to the channel members 28 by bolts 36. On the conduit sections 32 are secured'a plurality of vertically dispo'sed and spaced fins 31 to provide a sufficient amount of surface for the cooling of the condenser by natural draft circulation of air. It is to' be understood, however, that this ,condenser or one of any other suitable type may be cooled by forced circulation of air o'r other cooling fluid by the employment of a fan or other suitable device as is customary in the art. i

The lower end of thel condenser 3| is connected to one end of a U-shaped/refrigerant receiver 38,

the parallel ends of which lie alongside of the supporting plates`33 in order to minimize the interference with the circulation of air through the condenser. The oppo'site end of the receiver'is connected by a liquid line 39 to any suitable refrigerant evaporating unit 4| normally located within the heat insulated cabinet |1 and in the present instance comprising an expansion valve 42 which Adischarges vrefrigerant liquid into a refrigerant evaporating conduit 43. The suction line end of the evaporating conduit 43 is connected by a suction line 44 to the low pressure side of a refrigerant oompressor 46 embraced in a motor oompressor unit 41 of the refrigerating mechanism. The high pressure side of such compressor is connected to the inllet end 48 of the condenser 3|. t

The motor oompressor.` unit 41 comprises a compressor casing 45 and an integral cylindrical extension 43, the latter having three outwardly projecting legs 5| formed on the lower side thereof which are resiliently mounted on springs 52 having threaded bolts 53 projecting downwardly therethrough from the legs. Two of the Springs 52 are supported at their lower ends upo'n the upper surfaces of the channel members 28'while the remaining one is similarly supported upon a washer 54 disposed upon the upper surface of one of the angle members 21 and adjacent the middle thereof.

In order to prevent the Springs 52 from becoming impro'perly positioned between the legs 5| and the channel members 28 and washer 54 the opposite ends thereof are supported in cups 56 which in turn are seated against the aforesaid leg's and supporting members. i Beneath thev `face of the cylindrical extension 49 are disposed a plurality of spaced fins for increasing the heat exchanging surface of the extension and immediately inside thereof -is secured the stator 58 of an electric motor 59. The -rotor 6| of the motor 53 is rigidly secured upon a knurled surface 60 formed on a continuation of a hollow shaft oompressor 52 projecting from the compressor casing 45. The shaft is supported at one end in a bearing 83 formed in an end portion of a oompressor crankcase 54 while the opposite end thereof is supported in a bearing 66 formed at the inner extremity of a hollow part' 61 projecting inextension. The knurled exterior surface of the i aoaaavc shaft 62 provides a minimum amount of contact with the rotor 6| for restricting the flow of heat between such elementau In order to provide means for supporting the removable head 58, the

.14 of the head 68 is retained by studs 1|.

extension .49 is provided wtih an integral annular fiange 12 which supports a-compressible gasket 13 against which the outer fianged edge The inner -periphery of the fianged edge 'l4 of the head 68 is provided with a laterally 'extending flange 16 which. slidably and tightly engages the smooth inner edge of the annular end 12 of the extension 49 for -centering the head" 68 relative thereto. The head 68 is provided with radially extending webs 'l'l for reinfo'rcing the bearing 66 while the end of the crankcase 64 of thecom- 'pressor casing 45 is provided with similar radially extending webs 18 for reinforcing-the bearing 63.

' tion 81 of the casing head 68. The upper end of the stem 84 is surrounded by packing material 88 and is provided with a squared end 89 for operation by a wrench or other suitable tool (not shown). In order to insure against leakage of the'valve 82 and to protect the stem 84 from external injury, the upper end of the packing gland 86'is Vthreaded for receiving a cap 9| which completely encloses the upperiend of the packing gland and valve stem. The passage 83 comiunicates at one end with a gauge coupling 92 while the opposite end thereof communicates with a coupling 93 to which the suction line 44 is secured. Secured in an opening formed in an upper wall I of the inlet chamber 19 is a short pipe or conduit 94, the lower end of which'is curved laterally as is indicated at 96 and projects internally of the hollow shaft 62. This conduit is employed for the purpose of conducting oil to the interior of the hollow shaft from a sump 91 formed inside the around the inside of the extension 49 and become mediate its ends to the rotor 6| by rivets m2 coated with' oil collecting in the bottom thereof. This coating of 'oil is thrown from the blade by centrifugal force and is, distributed around the inside of the extension beyond the ends of the blades'and upon the exterior surfaces of the electric motor. Such of the oil as may collect upon the walls lof the casing above the sump 91 will drain downwardly into the sump and be conducted by the conduit 94' into the hollow shaft 52. Such oil as 'is splashed upon the-motor, later is also' spla'shed against the interior walls of the extension, where the heat absorbed thereby while in contact with the motor is dissipa'ted.

The oil distributing member is secured interprojecting through the rotor for securing the elements thereof together and the opposite ends of such rivets also e'ngage and secure to the rotor an annular thrust plate 103 which, engages the adjaeent end of the bearmg ss lfor umimig the l^ movement of the rotor in such direction.

In order to prevent the accumulation of oil on the side of the motor opposite the' blades 10|, the interior of the extension is provided with a channel |ll4 extending from one side of the motor to another for collecting and draining the oil away from such region. Also extending through `the rotor 5| of the motor 59 are a plurality of openings |85 which are formed therein in parallel relation to the axis of the motor for permitting circulation of gas from one side thereof to another. For supplying electrical energy to the 'motor 59 the extension 49 is provided with' an arcuate portion IDG of somewhat greater diameter vthan the remainder of the extension and which extends a short distance around the extension between the fianged end 1'2 thereofand the ad-' jacent one of the fins 55. i

` Extending across this enlarged portion and between the'studs 1| by which the head 88 is sev erally projecting portions to which theelectrical cenductors outside the 'extension are secured.

The inner nuts of the pairs ||2 are supported on washers U4 which in turn en'gage electrically insulating washers ||6 abutting the outer surface of the enlarged portion IOB of the extension and cooperating with the sleeves Ill to prevent the conduction of electrical energy elsewhere than through the bolts |08. The middle portions of the bolts |01 are square in cross-section as likewise are the sleeves and washers at the oppo-l site ends of the latter. The extension 49 around the outer limits of the enlarged portion IOS thereof is provided with a continuous-head H'l on the outer surface of which a terminal cover ||8 is secured by screws ll9. The cover, of course,l is provided with a suitable opening for the projection therein of the conductors to which the terminals Hl'l are attached; v

'I'he hollow shaft 62 within the bearings 63 and 56 is provided with'transverse openings |2I, the

outer ends of which communicate with oppositely disposed annular grooves 122 formediin the inner surfaces of the bearings. These openings conduct the oil from the interior of the hollow shaftfor lubricating the bearings.

Formed on the end of the compressor shaft 62 within the compressor easing 45 is an eccentric pin oncrank |24 on which one end of a connecting rod IIS is secured by a washer I 21 and a stud on the end of the shaft -62 by a plurality of studs VV |32. The plate |3| projects outwardlyl from the shaft 62 and abuts the adjacent end of the bearing 63 to provide a thrust bearing which, together with the annular ring 183, tends to limit movement of the motor shaft 82 in either direction. Between the heads of the studs. 32 and i the plate |3| and arranged to rotate inna cavity formed in the crankcase 64, is secured an edge portion of an arcuate balancing element 133', the outer edge of which is provided with radially disposed slots 134 forming tongues 136 which are bent backwardly and forwardly in opposite directions around an arcuate segment 131 formed of lead or some other heavy metal. This balancing element compensates for the eccentricweight of the pin 124, the connecting rod 126 and piston of the compressor and tends to pick up any oil with which it comes in' contact and to distribute it around the surface of the cavity 125.

The opposite end of the connecting rod 126 is provided with a bearing engaging a central portion of a pin 138 the opposite ends of which are secured by a key in internally disposed bosses formed in diametrical relation across the central portion of a piston 139. Formed in the compressor casing 45 above the crankcase 64 is an externally finned cylinder 141 in which the piston 139 is mounted for reciprocatory movement.

The crankcase 64 enclosing the rotating parts fordriving the compressor is closed by a removabie plate 143 secured to the open end thereof by studs 144. The 'crank casingl communicates with the interior of 'the shaft 62 by an openingformed axially thereof through the closed end of the shaft.

In order to provide lubrication for the connecting rod 126 and piston 139 the crank pin 124 isprovided with an opening 146 communicating at opposite ends with the passage 129 formed longitudinally thereof and with an annular groove 141 formed in the surface of the connecting rod bearing. This groove is formed directly opposite and in communication with a passage 148 formed lengitudinally of the connecting rod 126 for conducting oil to the 'pin 138 through intersecting circumferential and transverse grooves 140 and formed in the connecting rod bearing with which the opposite end of the passage communicates.

The lubrication for the piston 139 is provided by oil in Suspension in the working fluid of the refrigerating system upon which the compressor operates and by oil thrown from the weight 133.

Adjacent the upper limit of travel of the piston 139 the cylinder 141 is provided with a flat surface for supporting a valve plate 151 having disposed on the upper surfacethereof a head 152, in the interior of which is formed agas collecting chamber 153. The head and valve plate both' are secured rigidly to the cylinder 141 by cap screws 154. In order to provide for the operation of the compressor 46, the piston 139 and valve plate 151 are provided with suction and discharge valves 156 and 151 respectively.

, The suction valve 156 is formed by providing the head. end lf the piston 139 with a pair of annular and concentric recesses 158 and 159, the inner one of which communicates with a circular row of openings 161 which provide communication between the region in the cylinder 141 above and below the piston. An annular seat 162 formed hetweenthe recesses 168 and 159, and a boss 163 formed at the center of -the piston head are reduced in depth to a slight extent to provide seats for an annular disc 164 which is disposed in the head of the piston 139 within the limits of the upper surface thereof. In order to provide means for securing the disc 164 in position, the head of the piston 139 is provided with an axial opening having a bushing 166 disposed therein which is somewhat longer than the thickretaining cage 191.

ness of the piston head. Within this sleeve is received a bolt 161 having a head 168 which engages the upper surface of the disc 164 and retains the latter against .the upper end of the bushing 166. Theseparts are secured in such position by a nut 169 engaging the lower end of the bolt 161 and tightened against the lower end of the bushing 166. The lower end of the bolt 161 is upset against the lower surface of the nut 169 in order to prevent any of the parts from becoming loosened.

In the operation of the compressor when the direction of motion of the piston 139 is reversed adjacent its upper limit of travel, the inertia of the parts of theysuction valve 156 tends to slide the bushing 166 in the opening in the piston head until the nut 169 engages the lower surface of the latter, thus opening communication between the regions above and below the piston 139 through the opening 161 and between the annular seat 162 and the lower surface of the disc 164. The valve remains in this position during the downward movement of the piston 139 and the cylinder thereabove is filled'with thev working fluid within the refrigerating system which .is-supplied to the crank case 142 by the hollowtshaft 62. When the piston 139 reaches its lower limit of travel the reverse in the motion thereof seats the valve 156 upon the seats 162 and 163 and thereafter duririgl the upward movement of the piston the working fluid of the system previously admitted through the valve 156 is compressed within the cylinder 141 between the .piston 139 and the valve plate 151.

When the pressure in the cylinder has reached a predetermined value .the discharge valve 151 will operate and permit the compressed gas 'to be expelled from the'cylinder 141 into thegas colo iecting chamber l153 in the interior of the head.

' bolt 161, is provided with a circular row of spaced and transversely disposed openings 118 extending from one surface thereof to another in a region directly above the outer extremity of the suction valve disc 164. The upper surface of the plate is provided with three concentric and annular recesses 119,' 181 and 182 between which are vformed a pair of annular seats 188 and 184 and a centrally located boss 186. Theopenings 118 communicate with the central one of these annular recesses 131.

Upon the upper surfaces of the annular seats 183 and 184 is disposed a relatively fiexibie annular disc 181 which covers the annular recess 181 and the central portion of which engages an inwardly flanged portion 188 of a discharge valve The flanged portion 188 of the cage projects within the annular recess 182 and there engages the outer surface of the centrally disposed boss 186 formed on the valve plate 151, The outer periphery of the cage is provided with a radially disposed flange .192 formed at one side thereof which is disposed within the annular recess 119 and is secured rigidly therein by engagement beneath the lower surface ofthe head 152. l

Above the disc 181 is disposed an arcuate disc aosaave directly above the annular seat I83. 'Beyond the outer extremity of the arcuate disc |93 the cage |9| is provided with a. plurality of slots |94 through which gas or the working fiuid of the system may escape from beneath the cage.

The segments 190 'of the disc `|93 exert a presi sure upon the disc |8'1 which tends to retain the latter against the annular seats I83 and Hilll although this pressure is overcome and 'the disc |8'l is defiected off the annular seats when.` the pressure beneath the valve plate |5I, caused by' the upward movement of the piston |39, reaches a predetermined value. Thereafter the working fiuid of the system' is discharged through the space between the defiected .disc |81 and .the annular seat I83 until the piston reaches its upper limit of movement after which the disc again assumes its normal position upon the seat |93 and prevents the escape of the working fiuid .from the head |52 during the downward stroke of the piston. In the operation of the refrigerating systein disclosed herein the'working fluid of the system 'which may be any suitable 'refrigerant liquid, is

evaporated in the evaporating conduit 43 and such evaporated liquid or gas fills the suctlon conduit 44 and is drawn through the hollow shaft 92 into the interior of the crank case 64 at a relatively rapid rate by the reclprocation of the piston '39. I

The region in the interior of the extension 49, occuped by the motor 59, is also filled with this gas by reason of the connection of such compartment or region with the interior of the hollow shaft 62 through the conduit 96. 'However, inasmuch as there is practically no Variation in the size of this region during the. operation of the mechanism, there is 'practically no tendency for gas to fiow through the conduit 94; imles vthe pressure in the system changes, in which event enough gas will fiow through the conduit 94 to permit the pressure to equalize. Generally speaking, then, the gas surrounding the motor 59 in the extension 49 remains in a more or less isolated region and is 'therein continuously and v`iolent1y agitated by the rotation of the motor rotor 6| and the oil distributing member 99. The heat generated by the operation of the motor 59 is absorbed by this 'isolated quantity of gas and is conducted thereafter to the extension 49 from whence it is -dissipated into the surrounding air. When the'motor is not running, the gas in the extension 49 will cool to a considerable degree and some of it may either condense or disolve in the oil within the extension. When the operation of the'motor is again continued the evaporation of the refrigerant will greatly expand the oil as a result of the formation therein of numerous bubbles or small quantities of gas surrounded by liquid. In view of the large volume of the interior of the extension 49, however, this expanded oil will have plenty of space to occupy'without being discharged in'large quantitles through the pipe 94' into the hollow shaft 92. and,v even though some of it did gain access to the hollow shaft 62,

to fiow outwardly through the axial opening=|i40 and into the crank case and 'thereafter to' cause oil pumping by the compressor. While, during the operation vof the motor,the sta'gnant gas in the interior of the extension 49 becomes heated to 'a relatively high degree, this condition does not materially affect the principal parts of the motor .with which the gas is in contact other than to render possible the dissipation of a large quantity :of heat through the relatively limited exterior surface of the extension.

It is desirable, however; to maintain the bearingsof the 'motor at a considerably lower temperature than is permissi'ble in the other parts thereof, and this result is accomplishedtby having the relatively small amount of heat generated by the bearings directly absorbed by the gas from the evaporating unit which passes through the hollow shaft 62. There is not enough of such heat to materially change the temperature of vthe gas or to vcause any appreciable expansion thereof, by reason of the relatively limited space inside the shaft and the relatively large quantity of gas passing thcrethrough within such a short time and consequently only a small quantity 'of heat is absorbed by eacn unit of gas;

Inside the shaft 62 the particles of oil that may be carried by the gas are practically thrown outl of Suspension by the centrifugal force' caused by the rotation of the gas within the rotating shaft. Such separated oil collects around the inside of the shaft and eventually flows either through the openings |2 I` to the bearings 63 and 66, or through the passage 129 to the connectin'g rod and piston bearings. The oil, however, will not 'fiow |outwardly through the axially formed opening |40 where the gas is exhausted from the shaft 62 by same as the corresponding elements embraced in reason of its being held around the inner periph- 0 the preceding figures and, wherever applicable .the same reference numerals areapplied thereto.

In the structure disclosed by Fig. 14, there is employed inside the shaft 62 an insulating sleeve 2|0 for reducng the conductivity of heat from the motor and the bearings therefor to the refrigerant gas and oil during its passage through the shaft. The sleeve has openings communicating with the openings |2| in the shaft 62 to pro- Vvide for conductlng oil to the ;motor bearings,

and terminates slightlyz inside the closed end of sleeve not only tends to reduce the conductivity of heat to'the refrigerant and oil internally thereof but by reason of its greatly reduced internal diameter, as compared Iwith the corresponding diameter of the shaft 62, refrlgerant and oil will fiow through theshaft at a much greater ratel than were the sleeve not employed and hence the quantty of gas and. the time available for the .45 system fiows in a shunt circuit between the i and separating device. The motor compartment of ythe extension 49, in this instance, is entirely' closed by an end plate 2|| having no passage therethrougli for the admission of refrigerant.

Refrigerant and oil in Suspension therein is adi mitted' from the evaporator 4| through a valve 2|2 substantially identical to the valve employed pn the end plate 68 and formed integrally with an end plate 2|3 for closing the crank case 64. When so admitted the refrigerant vapor and oil separate by gravity in the crank case wherefrom the refrigerant vapor flows directly to the compressor 46. The oil collects in the bottom of the crank case and flows therefrom through the opening 199 to the motor compartment. There the oil will be distributed by the oil distributing member 99 over the surface of the motor for vcooling the latter and also collected in the sump 91 and circulated to the bearings of the motor and the compressor by the centrifugal force generated intemally of the shaft 62. By reason of the opening 199 the motor compartment also will be filled with vaporized refrigerant from the crank case 64 butithere will be no appreciablecirculation of refrigerant continuously between the crank case and the motor compartment. In this structure the opening M to provide for the flow of refrigerant between the interior of the shaft 62 and the crank case is not essential to the operation of the unit and may be eliminated if desired. It will lbe observed in this unit that the refrigerant vapor flows directly from the evaporating unit to the compressor through the crank case of the latter, whereas the greater portion of the oil in the various cooling surfaces and bearings of the motor compressor unit. i

While the structure as herein disclosed constitutes a preferred form and application of the invention, it is to be understood that there are numerous modified and equivalent structures also within the scope of the invention as 'defined by4 the appended claims.

I claim:

1. In a refrigerating system, a q motor compressor unit comprising a fluid fllled motor casing having a bearing formed therein, an electric motor therein, a shaft for said motor rotatably mounted in said bearing 'in said motor casing,

and means for cooling the coacting portions of -said bearing and shaft to a'greater extent than the remainder of said motor compressor' unit comprising means for circulating refrigerant and lubricant through said shaft, and dam means in said shaft maintaining a material amount of lubricant in said shaft during normal operation.

2..In a refrigerating system, a motor compressor unit comprising a motor casing having a working fluid passage therein, a motor and a compressor in said casing operatively connected together, said casing being adapted for the collection yof oil required for the lubrication of said motor and compressor, and oil displacing means having 'a bearing and an independent of said compressor and 'the suction effect thereof and driven by said motor for transferring the small quantities of said oil to said working fluid passage.

3. In a refrigerating system, a motor compressor unit comprising a motor casing having a working fluid passage therein and a compartment for the reception of an electric motor, said casing being adapted for the collection therein of oil required for the. lubrication of said motor, means for transferring small quantities of said oil from said casing to said working fluid passage, and means within said passage for centrifugally separating said oil from the working fluid therein.

4. In a refrigerating system, a motor compressor unit comprising a. casing having a refrigerant compressortherein and a working fluid passage for supplying refrigerant to said compressor and oil to the working parts of said unit, and ,means associated with said unit for` centrifugally separating said oil from said refrlgerant.

5. In a refrigerating system, a motor compressor unit comprising a casing having a pair of compartments formed' therein, an electric motor in one of said compartments, a compressor in the other of said compartments, means operatively connecting said motor and said compressor, the compartment for said motor being adapted for the collection of oil therein required for the lubrication of said motor and compressor, and rotatable means independent of said compressor and operated by said motor for removing small i quantities of oil from said casing;

6. In a refrigerating system, a motor compressor unit comprising a casing having a working fiuid passage arranged therein and a pair of compartments for the reception of .an electric motor and a compressor respectively, said compartment for said motor being adapted -for the collection of oil required for the operation of said motor, an oil distributing member in saidv motor-compartment vassociated with said motor for carrying away small quantities of said oil, a sump associated with said motor compartment for collecting some of 'the oil 'carried by said oil distributing member, and means for connecting .said sump with said working fluid passage.

7. In a refrigerating system, a motor compressor unit comprising a casing having an'electric motor mounted therein and av bearing for' said motor, a hollow shaft journaled in said bearing to be operated by said motor. means for supplying' working fluid with oil in Suspension therein to the interior of said hollow shaft, and meansv associated with one end of said shaft for maintaining a body ofoil in said shaft and preventing such oil from being discharged'from the corresponding end of said shaft.

8. In a refrigerating system, pressor unit comprising a motor having a hollow shaft, means for connecting said hollow shaft to a refrigerating system for receiving working fiuid with oil in Suspension therein from said system, means adjacent the terior thereof, and means adjacent the axis of said shaft for exhausting the working fluid of the refrigerating system therefrom.

inner periphery of said shaft for exhausting the oil from the in-- a motor com-3 aosm're centric pin extending beyond said bearing, a plate having an eccentric opening therein surrounding 'said pin and secured to said shaft in abutting relationto the adjacent end surface of said bearing and a refrigerant compressor operated by said pin. w

10. In a refrigerating system, a motor compressor unit comprising a crankcase having a relatively large extension' forming a motor compartment on one side thereof, said crankcase being of smaller diameter and concentrically arranged relative to said motor compartment, an electric motor in said motor compartment, a shaft rotatably mounted in said crankease and extending into said compartment for supporting said motor, a compressor cylinder formed in said crankcase associated therewith, a reciprocating piston in said cylinder and a connecting rod driven by said shaft for Operating said piston.

11. In a refrigerating system, a motor compressor unit comprising a compressor casing having an extension and providing a motor compartment and a compressor compartment, an electric motor mounted 'in said motor compartment, a refrigerant vcompressor in said compressor compartment, said compressor comprising a shaft journaled in said casing and associated with said motor and compressor for Operating the latter by the former, and a balancing element associated with said shaft and arranged in a cavity formed in said casing, the path of. movement of said element bing out of alignment with'the cylinder of said compressor whereby oil'collected by said element will be dischargedagainst said casing 'but not in direct contact with said' compressor cylinder.v

plate for securing the latter'to said casing, a plu-v v rality of terminals extending through said casing for providing an insulated electrical circuit therethrough for Operating said motor, said terminals being arranged in spaced relation around the periphery ofl said casing and extending theresor having an extension for receiving an electric motor, a bearing formed in the casingl of said compressor, a shaft mounted in said bearing and operatively associated with said motor and compressor, one end of said shaft having an eccen- :fluid and said electric motor.

15. In a refrigerating system a power unit comprising an electric motor and a refrigerant compressor having compartments for said motor and;`

compressor, means for admitting refrigerant vapor to be compressed to said compressor comi partment and means independent of the aforesaid means for forcibly circulating oil throughout said two compartments for lubricating said motor and compressor and forcooling the heat dissipating elements thereof. p

16. In a refrigerating system, a power unit including a compressor, a motor casing forming an extension of the casing for said compressor, a motor in said motor casing, a rotatable hollow shaft common to said motor and said compressor, means for introducing a refrigerant into one end of said shaft for passage' therethrough to said compressor, and means for feeding a lubx'icant into the interior of said shaft whereby 'said lubricant in being acted upon by centrifugal force due to the rotation of said shaft will form an insulating layer between the walls of saidshaft and said refrigerant'passing therethrough to reduce the rate of heat transfer betweensaidmotor and said refrigerant.

17. In a refrigerating system, a motor Vcompressor unitincluding an electric motor and a refrigerant compressor operatively connected together, said motor having a hollow shaft for the passage therethrough of the working fiuid operated upon by said compressor, and said shaft being insulated against the flow of heat between said working fluid and said electric motor.

JOHN R. REPLOGLE; 

